1. Field of the Invention
This invention relates to a connector for the use of electronic parts such as IC sockets in which a number of electronic contacting pieces must be arranged in high density and in parallel relation.
2. Description of the Prior Art
Heretofore, in the case where a number of electronic contacting pieces are to be arranged in high density and in parallel relation on a connector, the electronic contacting pieces are electrically isolated with respect to one another by a molded portion of the connector body forming an insulation body. For example, a plurality of accommodation chambers are defined in a connector body and adapted to accommodate a plurality of electric contacting pieces therein, a plurality of partition walls partitioning the accommodation chambers, the plurality of partition walls also adapted to isolate the electric contacting pieces from one another. Otherwise, a connector body may have an electric contacting piece planting body and a cover member with a plurality of holes formed therein, the electric contacting pieces, when the cover member is placed on the planting body, being accommodated in the plurality of holes formed in the cover member, the contacting pieces being isolated from one another by partition walls of the respective holes.
In an IC socket, as shown in FIG. 1 and FIGS. 2(A) through 2(C), a plurality of thin partition walls 3 are disposed in parallel relation with respect to one another around an IC accommodation space of a connector body 2 and a plurality of electric contacting pieces 1 are held in slits 4 formed between adjacent partition walls so that the electric contacting pieces are isolated from one another.
For example, in an IC package with leads as contacting point elements projecting sideward in parallel relation with respect to one another or in an IC package, etc. with conductive pieces as contacting point elements intimately attached to the outer surface of the insulation portion of the IC body, an electric contacting piece 1 having a vertically resiliently displacable contacting piece 1a, as exemplified in FIG. 2(A), is used in the IC socket. A resilient contacting point element L of the IC package is placed on the free end of the resilient contacting piece 1a and a pressure cover 2a is closed thereon to cause the electric contacting piece 1 to be resiliently displaced downward against the resilient force and resiliently contacted with the contacting point by its restoring force, and then locked and held by a lock member 2b engagable with the cover 2a.
The electric contacting piece 1 is planted in the bottom wall of a slit 4 formed between the partition walls 3 through a leg piece 1c connected to the resilient contacting piece 1a. The end portion of the leg piece 1c is projected downward so as to act as a connecting terminal for contacting with a wire board or the like. The connecting portion between the resilient contacting piece 1a and the leg piece 1c in the afore-mentioned planted state, is a supporting piece 1b laid along the bottom wall surface of the slit 4. The displacement of the electric contacting piece 1 is prevented, and the contacting point element L is stabilized with respect to the pressure contact.
As described in the foregoing, in the conventional connector for the use of electronic parts the connector is integrally formed with partition walls, to thereby isolate the electric contacting pieces from one another.
However, the electric contacting pieces of the connector for the use of electric parts are very tiny and the arranging pitch is also very small. Therefore, the partition walls are required to be formed very thin, and the molding technique for making the partition walls very thin already reaches the limit.
For example, the least pitch of a contacting point element of an IC package now in use is 0.65 mm pitch. If the isolation is to be achieved by the molded partition wall 3 and slit 4 as in the case of the conventional IC socket, and if the thickness of the electric contacting piece 1 is made as thin as 0.3 mm which is the thinnest available at present, and if the width of the slit is made 0.35 mm, taking play into consideration, the thickness of the partition wall 3 becomes as thin as 0.3 mm. If the partition wall 3 is as thin as 0.3 mm, resin does not sufficiently flow into the slit molding portion during the molding, or the molding fin is deformed by inflow pressure. As a result, inferior molding products are produced in which the end portions of the partition wall 3 are often broken or fell.
In the IC package, there is a tendency toward making the contacting point element much narrower and smaller in the future. Therefore, some effective counter-measures are required to be worked out rapidly as a common problem of a connector for the use of electronic parts.